1. Field of Invention
The present invention relates to an active solid-state device. More particularly, the present invention relates to multiple metal levels on a semiconductor, surrounded by insulating layers.
2. Description of Related Art
In electronics, an integrated circuit (IC) is a miniaturized electronic circuit (including semiconductor devices, as well as passive components) that has been manufactured in the surface of a thin substrate of semiconductor material. The first integrated circuit was developed in the 1950s by Jack Kilby of Texas Instruments and Robert Noyce of Fairchild Semiconductor. Hereafter, integrated circuits are used for a variety of devices due to their low cost and high performance.
In general, integrated circuits are fabricated simultaneously in multiples on a wafer. The wafer is sawed into individual chips once the fabrication is complete. Conventionally, the uppermost surfaces of the chips are generally protected by the deposition of a passivation layer. However, this passivation layer can not cover the periphery of each chip. Thus, the periphery of each chip is exposed to undesirable moisture and ionic contaminants. Accordingly, “seal rings,” also known as “guard rings,” generally are formed of at least one metal band around at least the upper periphery of each chip as part of the fabrication of the IC dice prior to sawing the wafer. These seal rings can provide structural reinforcement and stop undesirable moisture and mobile ionic contaminants from entering chip active circuitry regions and affecting operational reliability.